1. Field of the Invention.
The present invention relates to an expansion module and, more particularly, a universal expansion module system, method and apparatus for universally coupling a logic controller to a plurality of types of input/output expansion modules.
2. Related Information.
In the field of Logic Controllers, which include Programmable Logic Controllers (PLC) and Continuous Loop Controllers (CLC), for example, the Logic Controller is typically arranged in a rack configuration having a master controller coupled to one or more input/output (I/O) modules through a backplane that provides a common bus and a power source. The master controller is coupled through the I/O modules to various automation devices including, for example, motors, switches, turbines, boilers, etc. The entire composition of devices coupleable to the PLC is probably unlimited and those skilled in the art know well the various devices available for connection. In addition, the master controller is coupleable to other PLCs to form a master/slave arrangement whereby the master controller controls the slave controllers. Typically, the master controls the timing at which particular devices are to engage in operations and the slaves are responsible for carrying out the processing for driving the devices.
An object of the present invention is to provide a universal expansion module.
In accordance with the foregoing objectives, the present invention provides a universal expansion module apparatus for interfacing a logic controller to a plurality of types of input/output expansion modules that communicate input/output data between the controller and automated devices. A communication interface establishes communication between the controller and at least one of the plurality of types of an input/output expansion module. An expansion module having a physical configuration that accommodates signals from the plurality of types of input/output expansion modules.
The invention also provides a universal expansion module system. A logic controller has a configuration for driving an automated device. An input/output expansion module of a plurality of types couple the logic controller to the automated device. An expansion module has a physical configuration that accommodates signals from the plurality of types of input/output expansion.
The invention further provides a method for accommodating a logic controller to interface to a plurality of types of input/output expansion modules. In the novel method, there is the step of providing a common physical configuration for accommodating the plurality of types of input/output expansion modules. Next, there is provided establishing a first mode of operation to accommodate signals associated with a first type of input/output expansion module. Then, the step of establishing a second mode of operation is provided to accommodate signals associated with a second type of input/output expansion module.